| 摘要 |
The invention relates to a drill bit ( 2 ), having main cutting edges ( 4 a , 4 b) which are connected together by a transversal cutting edge ( 6 ). An open surface ( 7 ) which extends into a flute ( 8 ) lies adjacent to each main cutting edge. The drill bit ( 2 ) is ground, in particular, during a continuous three-dimensional grinding process in such a way that the open surface ( 7 ) forms a continuous curved surface which follows a radius of curvature (R) running from the main cutting edge ( 4 a) in the direction of the flute ( 8 ). The continuous grinding process, in comparison to a conventional two-stage process, produces an improved drill bit geometry which is devoid of ridges ( 16 ). The ridge-free configuration reduces the mechanical stress during drilling to a minimum. |
